1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
adoni [48]
3 years ago
6

The mean cost of domestic airfares in the United States rose to an all-time high of $385 per ticket (Bureau of Transportation St

atistics website, November 2, 2012). Airfares were based on the total ticket value, which consisted of the price charged by the airlines plus any additional taxes and fees. Assume domestic airfares are normally distributed with a standard deviation of $110.
a. What is the probability that a domestic airfare is $550 or more (to 4 decimals)?
b. What is the probability than a domestic airfare is $250 or less (to 4 decimals)?
c. What if the probability that a domestic airfare is between $300 and $500 (to 4 decimals)?
d. What is the cost for the 3% highest domestic airfares?
Mathematics
1 answer:
saveliy_v [14]3 years ago
7 0

Answer:

a)0.067

b)0.111

c)0.612

d)$687.28

Step-by-step explanation:

We are given the following information in the question:

Mean, μ = $385

Standard Deviation, σ = $110

We are given that the distribution of domestic airfares is a bell shaped distribution that is a normal distribution.

Formula:

z_{score} = \displaystyle\frac{x-\mu}{\sigma}

a) P(domestic airfare is $550 or more)

P(x > 550)

P( x > 550) = P( z > \displaystyle\frac{550 - 385}{110}) = P(z > 1.5)

= 1 - P(z \leq 1.5)

Calculation the value from standard normal z table, we have,  

P(x > 550) = 1 - 0.933 = 0.067= 6.7\%

b) P(domestic airfare is $250 or less)

P(x \leq 250) = P(z \leq \displaystyle\frac{250-385}{110}) = P(z \leq -1.22)

Calculating the value from the standard normal table we have,

P( x \leq 250) = 0.111 = 11.1\%

c))P(domestic airfare is between $300 and $500)

P(300 \leq x \leq 500) = P(\displaystyle\frac{300 - 385}{110} \leq z \leq \displaystyle\frac{500-385}{110}) = P(-0.77 \leq z \leq 1.04)\\\\= P(z \leq 1.04) - P(z < -0.77)\\= 0.851 - 0.239 = 0.612 = 61.2\%

P(300 \leq x \leq 500) = 61.2\%

d) P(X=x) = 0.03

We have to find the value of x such that the probability is 0.03.

P(X > x)

P( X > x) = P( z > \displaystyle\frac{x - 385}{110})=0.03

= 1 -P( z \leq \displaystyle\frac{x - 385}{110})=0.03

=P( z \leq \displaystyle\frac{x - 385}{110})=0.997

Calculation the value from standard normal z table, we have,  

\displaystyle\frac{x - 385}{110} = 2.748\\x = 687.28

Hence, the domestic fares must be $687.28 or greater for them to lie in the highest 3%.

You might be interested in
I would appreciate it if someone could help answer this problem:)
DedPeter [7]

Answer:

x=85^{\circ}

Step-by-step explanation:

The sum of the interior angles of any polygon with five sides is equal to (5-2)\cdot 180=3\cdot 180=540^{\circ}. Therefore, we can set up the following equation and solve for x:

115+95+115+130+x=540,\\455+x=540,\\x=\boxed{85^{\circ}}

5 0
3 years ago
(04.04)marcus painted one-third of his bedroom in fourth-fifths of an hour. at this rate, how long would it take him to paint th
4vir4ik [10]
The answere would be twelve fifths of an hour. 12/5 of an hour
5 0
3 years ago
Read 2 more answers
Write the expression as a product of expressions.
scoray [572]

Answer:

a^2(ab^{3}-b^{2}-c^{2})

Step-by-step explanation:

Given

a^{3}b^{3}-a^{2}b^{2}-a^{2}c^{2}

Required

Factor

a^{3}b^{3}-a^{2}b^{2}-a^{2}c^{2}

Factor out a^2

a^2(ab^{3}-b^{2}-c^{2})

<em>The expression cannot be further factored</em>

8 0
3 years ago
What are the slope and the y-intercept of the linear function that is represented by the table?
vlabodo [156]

Answer:

y=-2+12

Step-by-step explanation:

2ed row shows y int, suing x-x/y-y slope is -2

3 0
3 years ago
If the point (a,3) lies on the graph of the equation 5x + y = 8, then a=<br>a.01<br>b.0-1<br>c.0-7​
fomenos

Answer:

A (a = 1)

Step-by-step explanation:

A coordinate point is always in the form (x,y) that means the first point is always x-coordinate and the second point is always y-coordinate.

The equation given is:

5x + y = 8

The point is (a,3), so that means x = a and y = 3

We substitute the values into the equation and find a. Shown below:

5x + y = 8

5(a) + (3) = 8

5a + 3 = 8

5a = 8 - 3

5a = 5

a = 5/5

a = 1

Answer choice A is right

6 0
3 years ago
Other questions:
  • Elena bought 320 tropical fish for a museum display. She bought 7 times as many triggerfish as parrot fish. How many of each typ
    9·2 answers
  • Can u pls explain to me how to do this?​
    6·2 answers
  • What is the greatest common factor of 48 and 64
    8·1 answer
  • Find the slope of the line that passes through (4, 11) and (8, 10).
    11·1 answer
  • What is seven and seven eighths minus three and three eights
    8·2 answers
  • If m = 6 , and ( x , y ) = ( − 1 , − 3 ) , solve y = m x + b for b .
    7·1 answer
  • CAN SOMEONE HELP ME WITH THIS?????????????????????????????????????
    6·1 answer
  • Solve the quadratic equation. x2+2x−8=0
    7·2 answers
  • $70,000 - 17 1/2 % . <br>if i get this right i get the iphone xr​
    5·1 answer
  • Distribute the expression <br><br> -3(3+8s) =
    6·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!